The ability to identify human neural stem cells (NSC) by brain imaging may have profound implications for diagnostic, prognostic, and therapeutic purposes. Currently, there are no clinical, high-resolution imaging techniques that enable investigations of the survival, migration, fate, and function of unlabeled NSC and their progeny. The study of human NSC in vivo is hindered by the absence of well-defined markers that can distinguish them from other neural cell types. The goal of this proposal is to define markers of NSC by characterizing metabolomic fingerprint of NSC both in vitro and in vivo. Our objectives are to develop novel imaging and signal processing methodologies that would enable non-invasive investigations of NSC behavior in healthy and disease states, from early human development to older age. We hypothesize that mammalian NSC have a specific metabolic marker that can be identified by spectroscopy. Our specific aims are: 1) to characterize a metabolomic fingerprint of NSC in vitro using proton nuclear magnetic resonance (1H-NMR) spectroscopy and to compare it to the neuronal and glial 1H-NMR fingerprints; 2) to develop high resolution proton MR spectroscopy (1H-MRS) acquisition protocols that will allow for characterization of the NSC fate in vivo; 3) to develop signal processing algorithms that will provide accurate estimates of cell densities even from data with low signal-to-noise ratio and limited spectral, spatial, and temporal resolutions. Our preliminary experiments have demonstrated that we are able to identify the NSC on the basis of their 1H-NMR metabolomic fingerprint. In addition, we can detect both endogenous and exogenous NSC in the living rat brain, using 1H-MRS and 9.4T mMRI scanner. We plan to further characterize the metabolomic signature of NSC and other neural cell types, and to further perform metabolomic profiling of the living rat brain. The signal processing algorithms for identification, quantification, and tracking of NSC in vivo will be based on singular value decomposition methodology and will exploit prior knowledge gained from in vitro experiments. This innovative research will not only demonstrate the feasibility of using 1H-MRS spectroscopy for metabolomic investigations in vivo, but will also lead to a breakthrough in the field of stem cell research. Most importantly, this research is an essential prerequisite for future clinical investigations of NSC. The ability to monitor the fundamental changes of the NSC in the human brain will instigate new studies of neurological disorders where NSC pathology might contribute to the etiology of the disease and will initiate developments of new treatments. The proposed research is intrinsically multidisciplinary and involves collaborations of neuroscientists, physicists, engineers, chemists, and imaging scientists. Each of them will provide unique yet complementary expertise and resources available at the Stony Brook University and Brookhaven National Laboratory. [unreadable] [unreadable]